Cumberbatch is back in the intense new trailer for BBC’s Sherlock series four

Despite fans facing a wait until next year for season four of BBC’s hit show Sherlock, appetites will be partly whetted thanks to this first full trailer, heralding the return of London’s finest mystery solving duo.

This time around for Benedict Cumberbatch’s Holmes and Martin Freeman’s Watson, it doesn't look good as “everything they know will be tested”. Not least by Andrew Scott’s deceased Moriarty, clearly not letting a little problem like the afterlife stop him from springing a few more surprises.

Throw the masterful casting of Toby Jones as a new baddie into the mix and it could be something very special indeed.